dbconnect.java

java web网络编程示例,原代码资源

package edu.liusong.common;

import java.io.File;
import java.sql.*;
import java.util.Iterator;

import org.dom4j.Document;
import org.dom4j.DocumentException;
import org.dom4j.Element;
import org.dom4j.io.SAXReader;

public class DBConnect {
	private PreparedStatement ps = null;

	private ResultSet rs = null;

	private Connection conn = null;

	public DBConnect() {
		
		try {
			File dbProperty=new File(this.getClass().getResource("db.xml").getPath().replaceAll("%20", " "));
			SAXReader reader=new SAXReader();
			Document doc=reader.read(dbProperty);
			Element elements=doc.getRootElement();
			Element db;
			for(Iterator iter=elements.elementIterator("TABLE");iter.hasNext();){
				db=(Element) iter.next();
				String operation=db.attributeValue("operation");
				if(operation!=null&&operation.equals("1")){
					String driver=db.element("DRIVER").getStringValue();
					String url=db.element("URL").getStringValue();
					String database=db.element("DATABASE").getStringValue();
					String username=db.element("USERNAME").getStringValue();
					String password=db.element("PASSWORD").getStringValue();
					Class.forName(driver);
					conn = DriverManager.getConnection(url+database, username, password);
					break;
				}
			}
			
		} catch (ClassNotFoundException e) {
			e.printStackTrace();
		} catch (SQLException e) {
			e.printStackTrace();
		} catch (DocumentException e) {
			e.printStackTrace();
		}
	}
	
	public static void main(String args[]){
		try {
			new DBConnect();
		} catch (Exception e) {
			e.printStackTrace();
		}
	}

	public ResultSet executeQuery(String sql, String[] values) throws Exception {
		ps = conn.prepareStatement(sql);
		if (values != null) {
			for (int i = 0; i < values.length; i++) {
				ps.setString(i + 1, values[i]);
			}
		}
		rs = ps.executeQuery();
		return rs;
	}

	public int executeUpdate(String sql, String[] values) throws Exception {
		ps = conn.prepareStatement(sql);
		if (values != null) {
			for (int i = 0; i < values.length; i++) {
				ps.setString(i + 1, values[i]);
			}
		}
		return ps.executeUpdate();
	}

	public void close() throws SQLException {
		if (rs != null)
			rs.close();
		if (ps != null)
			ps.close();
		if(conn!=null)
			conn.close();

	}

	/*
	 * public static void main(String[] args) throws Exception { DBConnect con =
	 * new DBConnect(); // String sql="select * from user where name=?"; //
	 * String [] values={"liusong"}; // ResultSet rs=con.executeQuery(sql,
	 * values); // if(rs.next()){ // System.out.println(rs.getString(1)); //
	 * System.out.println(rs.getString(2)); //
	 * System.out.println(rs.getString(3)); // } // con.close();
	 * 
	 * String sql = "insert into user values(?,?,?)"; String[] values = {
	 * "12345576", "java", "java" }; con.executeUpdate(sql, values);
	 * con.close(); }
	 */

}